From patchwork Tue Dec 5 18:20:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13480581 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 63264C4167B for ; Tue, 5 Dec 2023 18:21:23 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.648195.1012360 (Exim 4.92) (envelope-from ) id 1rAa2P-0005oJ-4U; Tue, 05 Dec 2023 18:20:53 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 648195.1012360; Tue, 05 Dec 2023 18:20:53 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rAa2O-0005nc-Vd; Tue, 05 Dec 2023 18:20:52 +0000 Received: by outflank-mailman (input) for mailman id 648195; Tue, 05 Dec 2023 18:20:52 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rAa2O-0002wG-0I for xen-devel@lists.xenproject.org; Tue, 05 Dec 2023 18:20:52 +0000 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 03b80a54-939b-11ee-9b0f-b553b5be7939; Tue, 05 Dec 2023 19:20:49 +0100 (CET) Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-696-FJu31-KlP_-4-uDfX0zTIw-1; Tue, 05 Dec 2023 13:20:44 -0500 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 52F743C2A1CB; Tue, 5 Dec 2023 18:20:43 +0000 (UTC) Received: from localhost (unknown [10.39.194.111]) by smtp.corp.redhat.com (Postfix) with ESMTP id AF518492BE6; Tue, 5 Dec 2023 18:20:42 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 03b80a54-939b-11ee-9b0f-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701800448; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CXVutLONoGnwNzaaLHCyq57V4khRfPmIjmlvVDaOzsM=; b=Q6LP+B8SIvX1gS/60KXvRyKZKkKJaOhR3gvE9nI3lNHWsAtFvj3u0pta24hDl9dD7gwwNb 4pDwavhPpdw4ZGEB+GbRx6iZapvjlCHRA82MRPrHDpIYDnsTZSdXhI9LnXA1uwMANDDwpW n+2m1gpfAtEIdHZTZz8fKnqfmYnH+30= X-MC-Unique: FJu31-KlP_-4-uDfX0zTIw-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Stefan Hajnoczi , Vladimir Sementsov-Ogievskiy , Cleber Rosa , Xie Changlong , Paul Durrant , Ari Sundholm , Jason Wang , Eric Blake , John Snow , Eduardo Habkost , Wen Congyang , Alberto Garcia , Anthony Perard , "Michael S. Tsirkin" , Stefano Stabellini , qemu-block@nongnu.org, Juan Quintela , Paolo Bonzini , Kevin Wolf , Coiby Xu , Fabiano Rosas , Hanna Reitz , Zhang Chen , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Pavel Dovgalyuk , Peter Xu , Emanuele Giuseppe Esposito , Fam Zheng , Leonardo Bras , David Hildenbrand , Li Zhijian , xen-devel@lists.xenproject.org Subject: [PATCH v2 10/14] aio: remove aio_context_acquire()/aio_context_release() API Date: Tue, 5 Dec 2023 13:20:07 -0500 Message-ID: <20231205182011.1976568-11-stefanha@redhat.com> In-Reply-To: <20231205182011.1976568-1-stefanha@redhat.com> References: <20231205182011.1976568-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.10 Delete these functions because nothing calls these functions anymore. I introduced these APIs in commit 98563fc3ec44 ("aio: add aio_context_acquire() and aio_context_release()") in 2014. It's with a sigh of relief that I delete these APIs almost 10 years later. Thanks to Paolo Bonzini's vision for multi-queue QEMU, we got an understanding of where the code needed to go in order to remove the limitations that the original dataplane and the IOThread/AioContext approach that followed it. Emanuele Giuseppe Esposito had the splendid determination to convert large parts of the codebase so that they no longer needed the AioContext lock. This was a painstaking process, both in the actual code changes required and the iterations of code review that Emanuele eked out of Kevin and me over many months. Kevin Wolf tackled multitudes of graph locking conversions to protect in-flight I/O from run-time changes to the block graph as well as the clang Thread Safety Analysis annotations that allow the compiler to check whether the graph lock is being used correctly. And me, well, I'm just here to add some pizzazz to the QEMU multi-queue block layer :). Thank you to everyone who helped with this effort, including Eric Blake, code reviewer extraordinaire, and others who I've forgotten to mention. Signed-off-by: Stefan Hajnoczi Reviewed-by: Eric Blake Reviewed-by: Kevin Wolf --- include/block/aio.h | 17 ----------------- util/async.c | 10 ---------- 2 files changed, 27 deletions(-) diff --git a/include/block/aio.h b/include/block/aio.h index f08b358077..af05512a7d 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -278,23 +278,6 @@ void aio_context_ref(AioContext *ctx); */ void aio_context_unref(AioContext *ctx); -/* Take ownership of the AioContext. If the AioContext will be shared between - * threads, and a thread does not want to be interrupted, it will have to - * take ownership around calls to aio_poll(). Otherwise, aio_poll() - * automatically takes care of calling aio_context_acquire and - * aio_context_release. - * - * Note that this is separate from bdrv_drained_begin/bdrv_drained_end. A - * thread still has to call those to avoid being interrupted by the guest. - * - * Bottom halves, timers and callbacks can be created or removed without - * acquiring the AioContext. - */ -void aio_context_acquire(AioContext *ctx); - -/* Relinquish ownership of the AioContext. */ -void aio_context_release(AioContext *ctx); - /** * aio_bh_schedule_oneshot_full: Allocate a new bottom half structure that will * run only once and as soon as possible. diff --git a/util/async.c b/util/async.c index dfd44ef612..460529057c 100644 --- a/util/async.c +++ b/util/async.c @@ -719,16 +719,6 @@ void aio_context_unref(AioContext *ctx) g_source_unref(&ctx->source); } -void aio_context_acquire(AioContext *ctx) -{ - /* TODO remove this function */ -} - -void aio_context_release(AioContext *ctx) -{ - /* TODO remove this function */ -} - QEMU_DEFINE_STATIC_CO_TLS(AioContext *, my_aiocontext) AioContext *qemu_get_current_aio_context(void)